Abstract: Disclosed is a vest with adjustable tightness, which belongs to the technical field of clothes. The vest with adjustable tightness includes a garment body with shoulder straps and a zipper mounted, and also includes two adjusting belts, which are fixedly connected to the garment body, where the adjusting belts are erected on the shoulder straps, and two sides of a surface of the garment body are fixedly connected to mounting sheets; and two elastic bands, which are mounted on the back of the garment body, where the two elastic bands are distributed in a cross manner and form an X-shape. By rotating rotary knob disks, the elastic bands can be contracted and released, and the adjusting belts are tightened and loosened, such that sports personnel adjust tightness of the vest conveniently.